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Slayer Magic (
Slayer Magic is often regarded as a bit of an oxymoron- while it has been stated to have been "lost to the sands of time" (not the Prince of Persia which began the series' descent into 2edgy4u), but rather, all knowledge pertaining to it had been long forgotten. And yet, despite all odds, somehow it's easily the most utilized and known Lost Magic of all, with countless new upgrades and all that jazz being developed even now. In any case, more often than not, somebody is taught Slayer Magic by the creature the magic is named after, just like a martial arts master teaching their students- though of course, since it is magic, the creature is generally able to create a magical change in how the body's Magic Origin functions, therefore causing their body to possess the magical powers of their species; generally, the user's magical power acts alongside the energy of the body in order to catalyze a variety of bodily processes when younger, therefore allowing the morphing of their physiology to a point where the user has adopted some physical traits, as well as the element, from the said creature.
This always allows the user to produce and control their element from any part of their body, which can be used both in melee and as a ranged form of offense, turning their body into a makeshift weapon unique to themselves, greatly increasing the damage of their blows. A Slayer Magic generally has virtually unlimited customization options in regards to the element formed through simple magical manipulation- the colour, properties (not limited to but including heat, smell, and taste), and "feel" is capable of being modified to the user's liking for countless different effects and powers, more often than not being attuned to their own personality and ambitions; their "type" can be changed at will, and they can even be given a material consistency- the user is capable of utilizing it in any way they wish, whether for offensive, defensive, evasive, or supplementary techniques- as long as they can imagine it being doable, then the sky is the limit, more or less.
In addition, the user can consume external sources of their element to restore their body to a healthy state and regain their reserves of strength, something that also makes them immune to all types of their element, due to their capability of nullifying elemental-based attacks by sucking them in and eating them; the consumed element also seems to possess a different "taste" according to its "quality". However, the user can't eat their own element, or items which are affected by their element which they had set up to reinvigorate themselves. Slayer Magic can also be obtained by implanting Lacrima with a specific element into their body but tends to be weaker; and it can also be taught via grimoires. Finally, Slayer Magic is known to have a rather murky "tier system"- though this is only displayed in that Dragon Slayers cannot eat the element of a same-element God Slayer unless special precautions are taken.
Dragon Slayer Magic is a form of slayer magic which is (as the name suggests) taught by dragons and is used to slay dragons. The user can also utilize an element in battle such as fire, ice, steel and air etc.
Phoenix Slayer Magic is a form of Slayer Magic which is taught by phoenixes to slay their own kind. The user can utilize an element in battle. It is regarded as slightly weaker in terms of raw power to God Slayer; however, the user's wounds regenerate slowly over time, and the user does not need to consume an element to regain stamina, instead absorbing it the moment it is touched more than make up for this setback.
God Slayer Magic is a form of Slayer Magic which is taught by "gods" but can also be taught by another mage who knows this magic. It is used to slay "gods" like Dragon Slayer is used to slay dragons and it also has elemental styles.
Devil Slayer Magic, otherwise known as the Devil Slayer Curse, is a form of Lost Magic that is gained through a pre-existing user of the magic or by reading a Book of Zeref. It allows the user to employ elemental magic that enables them to deal a very high level of damage to Etherious and demons.
Spirit Slayer Magic is a form of Slayer Magic which is taught by spirits in order to slay them. The most notable of these is Celestial Spirits.